py-psycopg2: updated to 2.8.6

What's new in psycopg 2.8.6
- Fixed memory leak changing connection encoding to the current one.
- Fixed search of mxDateTime headers in virtualenvs.
- Added missing values from errorcodes.
- `cursor.query` reports the query of the last :sql:`COPY` opearation too.
- `~psycopg2.errorcodes` map and `~psycopg2.errors` classes updated to
  PostgreSQL 13.
- Added wheel packages for ARM architecture.
- Wheel package compiled against OpenSSL 1.1.1g.

What's new in psycopg 2.8.5
- Fixed use of `!connection_factory` and `!cursor_factory` together.
- Added support for `~logging.LoggerAdapter` in
  `~psycopg2.extras.LoggingConnection`.
- `~psycopg2.extensions.Column` objects in `cursor.description` can be sliced.
- Added AIX support.
- Fixed `~copy.copy()` of `~psycopg2.extras.DictCursor` rows

(adam)